diff --git a/build_info.json b/build_info.json
index 5e0d462..146b739 100644
--- a/build_info.json
+++ b/build_info.json
@@ -1,8 +1,8 @@
 {
     "build_time": "",
     "source files": {
-        "version": "v2.2.2-17",
-        "commit": "b78608767316f58ce04ceb6b23cf63ed9a382f00",
+        "version": "v2.2.2-18",
+        "commit": "1273d8c145b53ce155faa507b10b0b94616cffb3",
         "dirty": false
     },
     "pytex": {
@@ -144,9 +144,9 @@
         {
             "name": "mkessler-mathop.sty",
             "source file": "mathop.pysty",
-            "build time": "2021/10/25 20:46",
-            "source version": "v2.2.2-17",
-            "source commit hash": "b78608767316f58ce04ceb6b23cf63ed9a382f00",
+            "build time": "2021/10/25 20:48",
+            "source version": "v2.2.2-18",
+            "source commit hash": "1273d8c145b53ce155faa507b10b0b94616cffb3",
             "pytex version": "v1.0.0-18",
             "pytex commit hash": "126d420b7a6ed2d4b2a42d534ab2e12344869643",
             "dirty": false
diff --git a/math/mkessler-mathop.sty b/math/mkessler-mathop.sty
index 0db01cf..54083ce 100644
--- a/math/mkessler-mathop.sty
+++ b/math/mkessler-mathop.sty
@@ -27,7 +27,7 @@
 % 
 % Build details:
 %   PyTeX version: v1.0.0-18 (commit 126d420)
-%   Source code version: v2.2.2-17 (commit b786087)
+%   Source code version: v2.2.2-18 (commit 1273d8c)
 % 
 % This LaTeX package is free software and distributed under the MIT License. You
 % may use it freely for your purposes. The latest version of the package can be
@@ -256,4 +256,5 @@
 \newcommand\directlimit{\varinjlim}
 \newcommand\inverselimit{\varprojlim}
 
+\DeclareMathOperator*{\freeproduct}{\raisebox{-0.5ex}{\scalebox{2}{$\ast$}}}